Development of a Brief Screen to Detect Cognitive Impairment in Older Adults: The QuickSort

Abstract

BACKGROUND Sorting tests detect cognitive decline in older adults who have a neurodegenerative disorder, such as Alzheimerʼs and Parkinsonʼs disease. Although equally effective at detecting impairment as other cognitive screens (e.g. Mini‐Mental State Examination (MMSE)), sorting tests are not commonly used in this context. This study examines the QuickSort, which is a new brief sorting test that is designed to screen older adults for cognitive impairment. DESIGN Observational cohort study. SETTING General community and inpatients, Australia. PARTICIPANTS Older (≥60 years) community‐dwelling adults (n = 187) and inpatients referred for neuropsychological assessment (n = 78). A normative subsample (n = 115), screened for cognitive and psychological disorders, was formed from the community sample. MEASUREMENTS Participants were administered the QuickSort, MMSE, Frontal Assessment Battery (FAB), and Depression Anxiety and Stress Scale‐21. The QuickSort requires people to sort nine stimuli by color, shape, and number, and to explain the basis for their correct sorts. Sorting (range = 0–12), Explanation (range = 0–6), and Total (range = 0–18) scores were calculated for the QuickSort. RESULTS The Cognitively Healthy subsample completed the QuickSort within 2 minutes, 50% had errorless performance, and 95% had Total scores of 10 or greater. The likelihood of community‐dwelling older adults and inpatients (n = 260) being impaired on either the MMSE or FAB, or both, increased by a factor of 3.75 for QuickSort Total scores of less than 10 and reduced by a factor of 0.23 for scores of 10 or greater. CONCLUSION The QuickSort provides a quick, reliable, and valid alternative to lengthier cognitive screens (e.g., MMSE and FAB) when screening older adults for cognitive impairment. The QuickSort performance of an older adult can be compared with a cognitively healthy normative sample and used to estimate the likelihood they will be impaired on either the MMSE or FAB, or both. Clinicians can also use evidence‐based modeling to customize the QuickSort for their setting.

Use of the QuickSort with older adults whose lifestyle decision-making capacity is being questioned

“…On average, inpatients fell within the impaired range on the MMSE (<24; M = 23.1, SD = 4.3) and just above the cut-score for impairment on the FAB (<11; M = 11.6, SD = 3.4). The average QuickSort score in the Prospective-inpatient sample was <10 ( M = 6.5, SD = 5.7), which has previously been found to occur in as few as 4% of cognitively healthy older adults and has also proved to be the optimal cut-score for detecting impairment on the MMSE and FAB (Foran et al, 2021).…”

“…Greater certainty was associated with low (<2) and high (≥13) QuickSort scores, which increased or reduced the likelihood that a person lacked LS-DMC by a factor of 65.26 and 0.32, respectively. These categories also proved useful for detecting cognitive decline, with psychologically and cognitively-healthy older adults rarely scoring <2 and most (98%) scoring ≥13 (Foran et al, 2021). As is the case for many cognitive screens, it is therefore recommended that score categories be used to improve the accuracy with which the QuickSort is interpreted.…”

“…The QuickSort, which was only administered to the Prospective-inpatient group ( n = 76), required participants to sort nine cards by color, shape and number within a maximum of six trials. The QuickSort manual, stimuli and psychometric properties are published elsewhere (Foran et al, 2021). Total scores (range: 0–18) were calculated by summing: (1) a “Sorting” score, which aggregated the number of correct sorts (0 = correct without prompt; 1 = prompted, but correct; 2 = incorrect), sorting errors (repetition, set-loss, grouping or completion errors) and verbal prompts (range: 0–12); and (2) an “Explanation” score, which assessed the ability to verbalize the reason for the correct sort (0 = incorrect; 1 = concrete; 2 = correct, range: 0–6).…”

“…Total scores (range: 0–18) were calculated by summing: (1) a “Sorting” score, which aggregated the number of correct sorts (0 = correct without prompt; 1 = prompted, but correct; 2 = incorrect), sorting errors (repetition, set-loss, grouping or completion errors) and verbal prompts (range: 0–12); and (2) an “Explanation” score, which assessed the ability to verbalize the reason for the correct sort (0 = incorrect; 1 = concrete; 2 = correct, range: 0–6). Total scores <10 have previously been found to optimize sensitivity (82%) and specificity (78%) when trying to detecting impairment on either the MMSE, FAB, or both screens (Foran et al, 2021).…”

“…It includes multiple improvements to existing sorting tasks that enhance its usefulness (e.g., reduced administration & scoring time, early discontinuation for intact performance, larger range of impaired scores, freely available stimuli and A4 record form that provides instructions for administration and records all scores). The fact that the QuickSort has good inter-rater and test-retest reliability, has Australian norms for cognitively healthy older adults, and successfully predicts impairment on the MMSE and FAB, additionally supports its use as a brief cognitive screen (Foran et al, 2021). Whether the QuickSort is useful when interviewing patients with questionable LS-DMC, however, has yet to be determined.…”